Golf club head

ABSTRACT

A golf club head includes a front body formed of a metal material, an FRP body, a metallic sole plate, and a weight member. The front body has a face portion, a metal sole portion, a metal side portion (toe), a metal crown portion, a metal side portion (heel), and a hosel portion. A slight gap in a range of 4 mm to 12 mm is formed between a front side of the sole plate and the metal sole portion. This part is formed of the FRP body. Preferably, the weight of the front body is in a range of 20% to 70% of the weight of the golf club head.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a hollow golf club head, andparticularly to a golf club head being of a wood type or similar typethereto.

2. Description of the Related Art

As wood-type golf club heads such as drivers and fairway woods, metallicheads of a hollow shell structure are widely in use. Generally, thehollow wood-type golf club head has a face portion for hitting a ball, acrown portion constituting an upper surface portion of the golf clubhead, a sole portion constituting a bottom surface portion of the golfclub head, a side portion constituting side surface portions on the towside, the rear side, and the heel side of the golf club head, and ahosel portion. A shaft is inserted into the hosel portion, and is fixedby an adhesive agent or the like. It should be noted that golf clubscalled utility clubs are also commercially available on the market inlarge numbers, and various golf clubs having a head similar to theaforementioned wood-type golf club head (i.e., having the face portion,the sole portion, the side portion, the crown portion, and the hoselportion) are also commercially available on the market.

As metals for forming this hollow golf club head, an aluminum alloy,stainless steel, and a titanium alloy are used. The titanium alloy, inparticular, has come to be used widely in recent years.

In JP-A-2002-11122 and JP-A-2002-224249, the hollow golf club head inwhich the face portion is made of an amorphous alloy such as zirconiumgroup, and the other portions are metallic was described. In thesepatents, it was described that the face portion made of an amorphousalloy is useful to increase the carry.

Generally, it becomes possible to enlarge the sweet spot by increasingthe volume of the hollow golf club head. If the volume is increased, theweight of the golf club head tens to increase correspondingly.Accordingly, to prevent an increase in the weight, it has been conceivedto adopt a fiber reinforced plastic whose specific gravity is smallerthan those metals.

JP-A-2001-340499 discloses a golf club head in which a face portion anda sole portion are made of a metal, and the other portions including acrown portion and side portions on the tow side and the heel side areformed of a carbon-fiber reinforced thermosetting plastic (CFRP). If thecrown portion is made of CFRP, the flexure of the crown portion becomeslarge during ball hitting, so that it is possible to make the launchangle large, and increase a coefficient of restitution. With this golfclub head, however, the seam between a peripheral edge of the faceportion, on the one hand, and the crown portion and the side portionformed of CFRP, on the other hand, is in an abutted state. During ballhitting an extremely large stress occurs in this seam between theperipheral edge of the face portion and the crown portion and the sideportion. If the golf club head is used repeatedly, this joint portion islikely to peel off.

In the U.S. Pat. No. 6,471,604, a golf club head is described in whichthe crown front edge portion, the sole front edge portion, and both theside front edge portions are made to be a return portion made of anamorphous alloy, the face plane is a face plate made of an amorphousalloy, a latter half body (aft body) made of resin material is connectedto lead to the return portion, and an aluminum plate is disposed on thesole portion.

SUMMARY OF THE INVENTION

A first object of the invention is to provide a golf club head that iseasily designed in terms of a position of a center of gravity.

The golf club head as disclosed in U.S. Pat. No. 6,471,604 has a smallflexure on the sole side when hitting the ball, because the aluminumplate on the sole portion leads directly to the bottom of the returnportion. A second object of the invention is to provide a golf club headhaving a large flexure on the sole side when hitting the ball, and alarge restitution coefficient.

To achieve the above objects, according to one aspect of the invention,there is provided a golf club head of a hollow shell structure,including: a first member that includes an amorphous metal material andincludes a hosel portion, a face portion and an edge portion continuouswith the face portion; a metal plate that is different member from thefirst member, extends in a direction, which is different from a toe-heeldirection of the golf club head, and includes at least a part of soleportion; and a second member formed of a fiber reinforced 20% to 70% ofweight of the golf club head.

According to another aspect of the invention, there is provided a golfclub head of a hollow shell structure, including: a first member thatincludes an amorphous metal material and includes a face portion and anedge portion continuous with the face portion; a metal plate that isdifferent member from the first member, extends in a direction, which isdifferent from a toe-heel direction of the golf club head, and includesat least a part of sole portion; and a second member formed of a fiberreinforced plastic, wherein the first member and the metal plate areapart from each other, and the second member joints the first memberwith the metal plate.

In the golf club head of the invention, the weight of the first memberis in a range of 20% to 70% of the weight of the golf club head. Sincethe second member is made of the fiber reinforced plastic, which has thesignificantly smaller specific gravity than that of metal, a weightother than the first member can be allocated to the metal plate and aweight member disposed on the metal plate. Thereby, the golf club headcan be easily designed to have a center of gravity at lower position oron a rear side, and so on as desired.

In the golf club head of the invention, a portion between the firstmember made of amorphous metal and the metal plate is flexed whenhitting a ball, whereby the coefficient of restitution is great and acarry of the ball is increased.

Preferably, the portion of the second member between the first memberand the metal plate recesses from the metal plate and a bottom surfaceof the first member. By virtue of this arrangement, even if a solesurface of the golf club head strongly strikes the ground, the portionis difficult to become damaged.

Since the second member is fixed on the edge portion in a superposedstate, the first member and the second member can be firmly fixedtogether.

Since a back face of the first member is lined with the fiber reinforcedplastic, the first member can be reinforced or made less flexible.

Preferably, widths of a crown portion and a sole portion of the firstbody are larger on a toe side and a heel side than those of a centralportion between these portions. By virtue of this arrangement, themoment of inertia of the golf club hear can be made large.

The invention is suitable for application to a large-size driver headwhose weight needs to be suppressed to 180 g -210 g or thereabouts,although its volume is large in a range of 300 cc-500 cc.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a golf club head in accordance with theembodiment;

FIG. 2 is a perspective view, as taken from the front side, of a frontbody and a sole plate of this golf club head;

FIG. 3 is a perspective view, as taken from the rear side, or the frontbody;

FIG. 4A is a plan view of this golf club head;

FIG. 4B is a bottom view of this golf club head;

FIG. 5A is a section view taken along line V-V in FIG. 4A;

FIGS. 5B and 5C are enlarged views of a portion B and a portion C inFIG. 5A;

FIG. 6 is a section view illustrating a method of manufacturing thisgolf club head;

FIG. 7A to 7E are explanatory diagrams of prepreg sheets used in themanufacture of an FRP body of this golf club head; and

FIG. 8 is a section view of a golf club head according to anotherembodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereafter, a description will be given on an embodiment of the inventionwith reference to the drawings. FIG. 1 is a perspective view of a golfclub head in accordance with the embodiment. FIG. 2 is a perspectiveview of a front body and a sole plate of this golf club head as viewedfrom a front side. FIG. 3 is a perspective view of the front body asviewed from a rear side. FIG. 4A is a plan view of this golf club head.FIG. 4B is a bottom view of this golf club head. FIG. 5A is a sectionview taken along line V-V in FIG. 4A. FIGS. 5B and 5C are enlarged viewof a portion B and a portion C in FIG. 5A. FIG. 6 is a section viewillustrating a method of manufacturing this golf club head. FIGS. 7A to7E are explanatory diagrams of prepreg sheets used in the manufacture ofan FRP body of this golf club head.

This golf club head 1 is a wood-type golf club head of a hollow shellstructure including a face portion 2, a sole portion 3, a side portion4, a crown portion 5, and a hosel portion 6.

The face portion 2 is a surface for hitting a ball, and is provided withgrooves (scoring lines), which are not shown. The sole portion 3constitutes a bottom portion of the golf club head. The side portion 4constitutes side surface portions on the toe side, the heel side, andthe rear surface side. The crown portion 5 constitutes an upper surfaceportion of the golf club head. A shaft is inserted into the hoselportion 6, and is secured by means of an adhesive agent.

This golf club head 1 includes a front body 10 formed of an amorphousmetal material, a fiber reinforced plastic body (hereinafter referred toas the FRP body) 20, a metallic sole plate 30, and a weight member 40.The weight of this front body 10 is preferably in a range of 20% to 70%,especially 30% to 60% of the total weight of the golf club head.

As shown in FIGS. 2 and 3, the front body 10 includes the face portion2, a metal sole portion 13, a metal side portion (toe) 14, a metal crownportion 15, a metal side portion (heel) 16, and a hosel portion 6.

The metal sole portion 13 constitutes a front edge portion of the soleportion 3. The metal side portions 14 and 16 constitute front edgeportions of the side portion 4. The metal crown portion 15 constitutes afront edge portion of the crown portion 5. The metal crown portion 15 iscontinuous with the metal side portion (toe) 14 and the metal sideportion (heel) 16. The metal side portion (toe) 14 and the metal sideportion (heel) 16 are respectively continuous with the metal soleportion 13. The metal side portions 14 and 16 and the metal sole portion13 are continuous with the face portion 2.

As for the metal sole portion 13 and the metal crown portion 15, widthsin the forward and rearward direction (widths in a directionperpendicular to the face portion 2) are large on the tow side and theheel side, and their widths in the forward and rearward direction in theremaining central portions 13 a and 15 a are small. As a result, themoment of inertia of the golf club head can be made large. It should benoted that these widths in the forward and rearward direction are madegradually smaller from the toe side and the heel side toward the centralportions 13 a and 15 a.

The length in the toe-heel direction of the center portions 13 a and 15a having small widths in the forward and rearward direction ispreferably 50%-85% of the maximum width of the front body 10 in thecrown portion, and is preferably 55%-80% of the maximum width of thefront body 10 in the sole portion.

The width of the central portion 15 a of the metal crown portion 15 inthe forward and rearward direction is preferably 50%-95%, particularly55%-70% of the maximum width of the front body 10 in the forward andrearward direction, while the width of the central portion 13 a of themetal sole portion 13 in the forward and rearward direction ispreferably 50%-95%, particularly 55%-65% of the maximum width of thefront body 10 in the forward and rearward direction.

A gap of 4 mm-12 mm, particularly 7 mm-9 mm is formed on an averagebetween a front side 31 of the sole plate 30 and the metal sole portion13, as clearly shown in FIGS. 5A and 5C. The FRP body 20 is interposedbetween these two members. The FRP body 20 between the metal soleportion 13 and the front side 31 of the sole plate 30 is upwardlyrecessed from the bottom surfaces of the metal sole portion 13 and thesole plate 30. The average depth of this recess is preferably 0.7 mm-1.5mm. Since the FRP body 20 is thus recessed, the FRP body 20 is preventedfrom becoming damaged by strongly striking the ground during a duffshot. The bottom of the FRP body 20 at this recessed portion is curvedin an arch shape in the forward and rearward direction of the golf clubhead, as shown in FIG. 5C.

A rear side 34 of the sole plate 30 is located in proximity to arearmost portion of the golf club head 1, but is located slightlyforwardly of the rearmost end of the golf club head 1.

The sole plate 30 is disposed in a whole area in the vicinity of thecentral portion, in the toe-heel direction, of the metal sole portion13. As shown in FIG. 2, this sole plate 30 has a substantiallyquadrangular shape having the front side 31 facing the metal soleportion 13, sides 32 and 33 extending in the rearward direction fromboth ends of the front side 31, and the rear side 34. The front side 31is longer than the rear side 34, and the sides 32 and 33 approach eachother toward their rear sides. Accordingly, the sole plate 30 issubstantially trapezoidal in a plan view shape. The sole plate 30 iscurved in conformity with the sole surface of the golf club head 1.

The length of the front side 31 of the sole plate 30 is preferably50%-75%, particularly 60%-75% of the length in the toe-heel direction ofthe central portion 13 a of the metal sole portion 13. The length of therear side 34 is preferably 50%-80%, particularly 55%-75% of the lengthof that front side 31.

The length of the sole plate 30 in the forward and rearward direction ispreferably 65%-90%, particularly 75%-85% of the maximum length of thegolf club head 1 in the forward and rearward direction.

This sole plate 30 is formed of a metal material such as stainlesssteel, aluminum, a copper alloy, a titanium alloy, or the like.

A cylindrical portion 35 protrudes in a rear portion of this sole plate30 toward the interior of the golf club head 1. The weight member 40 issecured in an inner hole of the cylindrical portion 35 by screwing-in.

The weight member 40 is formed with a flange portion 41 on a lower endthereof. The cylindrical portion 35 is formed with a stepped portion 35a for receiving the flange portion 41 at a lower edge thereof.

The sole plate 30 is slightly depressed around the periphery of thecylindrical portion 35.

The weight member 40 is formed of a metal whose specific gravity isgreater than that of the sole plate 30, such as tungsten or a tungstenalloy. The specific gravity of the weight member 40 is preferably 10 ormore, particularly in a range of 10 to 13. The central position of theweight member 40 is located on a rear portion side of a center of thegolf club head 1 in the forward and rearward direction.

Next, a description will be given on a method for manufacturing the golfclub head according to the embodiment of the invention.

To manufacture this golf club head 1, the metallic front body 10, thesole plate 30, and a plurality of prepreg sheets are used. A connectingface between the front body 10 and the FRP body 20 is desirably treatedby blasting or spray coating to enhance the connectivity.

FIGS. 7A to 7E are plan view illustrating the prepreg sheets adopted inthis embodiment. A prepreg sheet 51 shown in FIG. 7A is one in which acarbon fiber cloth is impregnated with a thermosetting synthetic resin.Prepreg sheets 52, 53, 54 and 60 shown in FIGS. 7B, 7C, 7D and 7E arethose in which carbon fibers are oriented in one direction and areimpregnated with the thermosetting synthetic resin. The prepreg sheets51 to 54 constitute the lower half side of the FRP body 20, and arerespectively provided with circular openings 50 for allowing thecylindrical portion 35 of the sole plate 30 to pass therethrough.

The prepreg sheet 51 is directly superposed on the sole plate 30, andhas a substantially trapezoidal shape, which is slightly larger than thesole plate 30.

The prepreg sheets 52, 53 and 54 are directly superposed on the prepregsheet 51 in that order. In order to constitute the lower half of the FRPbody 20, each of these prepreg sheets 52 to 54 has such a size that thelower half of the FRP body 20 is developed. A plurality of slits 55 arecut in both sides and rear edges of these prepreg sheets 52 to 54 atpredetermined intervals, so that the sides and the rear edges of theprepreg sheets 52 to 54 are easily curved along the inner surface of amolding die.

In the case of the prepreg sheet 52, the carbon fibers are oriented inthe toe-heel direction. In the case of the prepreg sheet 53, the carbonfibers are oriented obliquely to the toe-heel direction 60° clockwise.In the case of the prepreg sheet 54, the carbon fibers are orientedobliquely to the toe-heel direction 60° counterclockwise.

The prepreg sheet 60 is used for constituting the upper surface side ofthe FRP body 20 and is formed with a substantially semicircular notchedportion 61, with which the hosel portion 6 engages.

In manufacturing of the golf club head 1, the sole plate 30 is firstfitted in the die having a cavity surface conforming to the sole andsides. The prepreg sheets 51 to 54 are superposed in that order. Then,these prepreg sheets 51 to 54 are semihardened on heating for a shorttime, so as to be formed into the shape of a sole portion 22 of the FRPbody 20 and to be integrated with the sole plate 30, as shown in FIG. 6.

The prepreg sheet 60 is also fitted in the die having a cavity surfaceconforming to the crown portion, and is semihardened on heating for ashort time, so as to be formed into the shape of a crown portion 21 ofthe FRP body 20, as shown in FIG. 6.

Subsequently, the prepreg sheet 60, the prepreg sheets 51 to 54 with thesole plate and the metallic front body 10 are 1.

At this time, the front edge of the crown portion 21 formed of theprepreg sheet 60 is superposed on the lower surface of the metal crownportion 15 (inner side surface of the head). In addition, the front edgeof the sole portion 22 formed of the prepreg sheets 51 to 54 issuperposed on the upper surface of the metal sole portion 13 (inner sidesurface of the head). It should be noted that the front edge of the soleportion 22 projects forwardly of the front side 31 of the sole plate 30,and the rear edge of the sole portion 22 projects rearwardly of the rearside 34 of the sole plate 30, as shown in FIG. 6. The rear edge of thecrown portion 21 is superposed on the outer surface of the rear edge ofthis sole portion 22.

Next, the molding die is heated, and gas pressure of air or the like isintroduced into the molding die through the cylindrical portion 35. Thiscauses the crown portion 21 and the sole portion 22 formed of thesemihardened prepreg sheets to be pressed against the inner surface ofthe molding die, the prepreg sheets to become fully hardened, the crownportion 21 and the sole portion 22 to be secured to the front body 10,and the crown portion 21 and the sole portion 22 to be joined together.

During this molding, part of the synthetic resin in the prepreg sheetsenters the gap between the metal sole portion 13 and the sole plate 30,and the recessed portion in which the FRP body 20 is curved in the archshape is formed, as shown in FIG. 5C.

Subsequently, the molded piece is released, the weight member 40 isthreadedly secured to the cylindrical portion 35, and finishing such asdeburring and coating is performed to form the product golf club head.

With the golf club head thus constructed, since all the portionscontinuous with the front body 10, including the portion between thefront body 10 and the sole plate 30, are formed of FRP, the head can beeasily flexed and have high repulsion during ball hitting. At the sametime, the center of gravity can be made deep. In particular, in thisembodiment, since the crown portion of the FRP body 20 is easily flexed,the launch angle can be made large, and the flight distance can beincreased.

Since the FRP body 20 is superposed and fixed on the inner face of themetal sole portion 13, the metal crown portion 15 and the metal sideportion 14 of the front body 10, the connection strength between thefront body 10 and the FRP body 20 is high. The foremost edge of the FRPbody 20 is preferable to contact with the face portion 2.

In this invention, the amorphous metal material is not specificallylimited in its composition, as long as it has a supercooling liquidzone, and can form an amorphous phase. Hence, various amorphous metalmaterials can be employed, but preferably have the compositionrepresented by the general formula of MaXb (a and b are atom %,65≦a≦100, 0≦b≦35).

Herein, M is al least one selected from the group consisting of Zr, V,Cr, Mn, Fe, Co, Ni, Cu, Ti, Mo, W, Ca, Li, Mg, Si, Al, Pd, and Be, and Xis at least one selected from the group consisting of Y, La, Ce, Sm, Md,Hf, Nb, TaAg, Pt, Au, and Pd. Particularly, a Zr-based amorphous alloy(having the greatest atom % of Zr) is desirable. With the Zr-basedamorphous alloy, the amorphous structure is relatively easily produced,even if the cooling speed is reduced. The amorphous alloy is notnecessarily composed of a single phase of a pure amorphous alloy, butmay contain from several vol % to several tens vol % ofmicro-crystalline or quasi-crystalline phase that can be produced underthe manufacturing conditions or heat treatment for an amorphous alloy.

The amorphous alloy is more prone to crack beyond an elastic limit, asthe non-crystallinity is higher. Thus, to suppress the flexure at thetime of batting the ball, it is preferable to dispose the fiberreinforced plastic layer on the back face of the face portion 2 as well,as shown in FIG. 8. Carbon fiber, and organic fibers such as glass fiberand aramid fiber are usable.

The other constitution of FIG. 8 is the same as that of FIG. 5A. Thesame reference numerals are used to designate the same parts.

The non-crystallinity of an amorphous alloy is from 75%-100%, orpreferably from 80%-98%, at least on the face portion. If thecrystallinity is lower than 75%, there is a fear that the strength ofthe face portion may be insufficient. If the crystalline phase exists ina part of amorphous metal, the plastic deformation is allowed, wherebythe amorphous metal is superior in terms of the workability andstrength.

PRACTICAL EXAMPLE

In a golf club having the golf club head of the embodiment that ismanufactured by way of trial using a zirconia-based amorphous alloy, acenter of a face was batted at a ball speed of 40 m/s, 500 shots, usingtwo piece of golf ball, whereby strength evaluation was conducted.

Thickness of face was 3 mm. Also, workability evaluation for theamorphous metal was conducted based on whether the polishing is easy ornot.

As a result, it was found that if the non-crystallinity is 75% or more,especially 80%, strength of the amorphous metal in the head issufficiently high. Also, it was found that the workability issufficiently excellent if the non-crystallinity is 60% or more, andremarkably excellent if it is 98% or less.

COMPARATIVE EXAMPLE

It is preferred that an amorphous alloy making a face portion in theembodiment has lower Young's modulus than that of a titanium alloy, andhas a breakdown characteristic equal to or stronger than that of thetitanium alloy.

By making a face portion A with the amorphous alloy having the breakdowncharacteristic equal to or stronger than that of the titanium alloy, itis possible to configure a thickness of the face portion A in a range of2.3 mm to 2.9 mm. Moreover, by making the face portion A with theamorphous alloy having Young's modulus in a range of 7000 kgf/mm² to9000 kgf/mm², preferably 7200 kgf/mm² to 8500 kgf/mm², the face portionA becomes flexible when hitting a ball, and make an initial velocity ofthe ball faster even the thickness of the face portion A is equal tothat of a face portion B made of titanium alloy.

However, when the thickness of the face portion A is configured to be2.6 mm and Young's modulus thereof is 5000 kgf/mm², it is too flexiblethat the initial velocity of the ball becomes slower than that whenhitting the ball with the face portion B made of the titanium alloy.

The breakdown characteristic of the amorphous alloy is preferably equalto or stronger than that of a common titanium alloy (Ti-6Al-4V). If thebreakdown characteristic of the amorphous alloy is lower than that ofthe common titanium alloy, the thickness of the face portion A needs tobe thicker so that a flexure of the face portion A can not be fully usedwhen hitting the ball even Young's modulus of the amorphous alloy is setlower than that of the common titanium alloy. Correspondingly, theinitial velocity of the ball cannot be faster. Therefore, the equal toor more than 80 kgf/mm², especially in a range of 100 kgf/mm² to 160kgf/mm².

A thickness of a central portion of the face portion A is configured tobe in a range of 2.3 mm to 2.9 mm, a thickness of a peripheral portionof the face portion A connecting to a crown portion and the sole portionis configured to be in a range of 1.3 mm to 1.6 mm so as to be thethinnest portion in the face portion A. By this configuration, strengthof a hitting portion becomes stronger and a repulsive force becomeslarger. The peripheral portion of the face portion A is preferably in arange of 0.5 mm to 5 mm.

Herein, comparative experiments are conducted with three materials.Material I is employed in the embodiment. Material II and III arecomparative examples.

The result of a comparison, a carry of a ball is longest when the ballwas hit by a golf club head having a face portion made of Material I.And a carry of the ball is shortest when the ball was hit by a golf clubhead having a face portion made of Material II. Young's Breakdownmodulus Characteristic Thickness Material (kgf/mm²) (kgf/mm²) (mm) IZirconium-based 7200 to 8000 130 to 150 2.6 amorphous alloy 11000 1122.6 II Titanium alloy (Ti-6Al-4V) III Zirconium-based 5000 to 6000 130to 150 2.6 amorphous alloy

The foregoing description of preferred embodiments of the invention hasbeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed, and modifications and variations are possible in light of theabove teachings or may be acquired from practice of the invention. Theembodiments were chosen and described in order to explain the principlesof the invention and its practical application to enable one skilled inthe art to utilize the invention in various embodiments and with variousmodifications as are suited to the particular use contemplated. It isintended that the scope of the invention be defined by the claimsappended hereto, and their equivalents.

1. A golf club head of a hollow shell structure, comprising: a firstmember that includes an amorphous metal material and includes a hoselportion, a face portion and an edge portion continuous with the faceportion; a metal plate that is different member from the first member,extends in a direction, which is different from a toe-heel direction ofthe golf club head, and includes at least a part of sole portion; and asecond member formed of a fiber reinforced plastic, wherein weight ofthe first member is in a range of 20% to 70% of weight of the golf clubhead.
 2. A golf club head of a hollow shell structure, comprising: afirst member that includes an amorphous metal material and includes aface portion and an edge portion continuous with the face portion; ametal plate that is different member from the first member, extends in adirection, which is different from a toe-heel direction of the golf clubhead, and includes at least a part of sole portion; and a second memberformed of a fiber reinforced plastic, wherein the first member and themetal plate are apart from each other, and the second member joints thefirst member with the metal plate.
 3. The golf club head according toclaim 1, wherein the amorphous metal material is a zirconium alloy. 4.The golf club head according to claim 1, wherein the non-crystallinityof the amorphous metal material is in a range of 75% to 100% in the faceportion.
 5. The golf club head according to claim 1, wherein a portionof the second member between the first member and the metal platerecesses from the metal plate and a bottom surface of the first member.6. The golf club head according to claim 1, wherein the metal plate ismade of a metal material, which is larger in specific gravity than theamorphous metal material.
 7. The golf club head according to claim 2,wherein the amorphous metal material is a zirconium alloy.
 8. The golfclub head according to claim 2, wherein the non-crystallinity of theamorphous metal material is in a range of 75% to 100% in the faceportion.
 9. The golf club head according to claim 2, wherein a portionof the second member between the first member and the metal platerecesses from the metal plate and a bottom surface of the first member.10. The golf club head according to claim 2, wherein the metal plate ismade of a metal material, which is larger in specific gravity than theamorphous metal material.
 11. The golf club head according to claim 10,wherein the metal material of the metal plate includes stainless steel.12. The golf club head according to claim 1, further comprising: aweight member that is fixed to the metal plate and is larger in specificgravity than the metal plate.
 13. The golf club head according to claim2, further comprising: a weight member that is fixed to the metal plateand is larger in specific gravity than the metal plate.
 14. The golfclub head according to claim 12, wherein the metal plate defines acylindrical portion to which the weight member is fixed.
 15. The golfclub head according to claim 13, wherein the metal plate defines acylindrical portion to which the weight member is fixed.
 16. The golfclub head according to claim 1, wherein the second member is fixed onthe edge portion in a superposed state.
 17. The golf club head accordingto claim 2, wherein the second member is fixed on the edge portion in asuperposed state.
 18. The golf club head according to claim 1, wherein aback face of the first member is lined with the fiber reinforcedplastic.
 19. The golf club head according to claim 2, wherein a backface of the face portion is lined with the fiber reinforced plastic. 20.The golf club head according to claim 1, wherein the first memberincludes a crown portion and a sole portion, and widths of the crownportion and the sole portion of the first member on a heel side and atoe side are larger than that in a center portion thereof.
 21. The golfclub head according to claim 2, wherein the first member includes acrown portion and a sole portion; and widths of the crown portion andthe sole portion of the first member on a heel side and a toe side arelarger than that in a center portion thereof.
 22. The golf club headaccording to claim 1, wherein volume of the golf club head is in a rangeof 300 cc to 500 cc; and the weight of the golf club head is in a rangeof 180 g to 210 g.
 23. The golf club head according to claim 2, whereinvolume of the golf club head is in a range of 300 cc to 500 cc; andweight of the golf club head is in a range of 180 g to 210 g.
 24. Thegolf club head according to claim 1, wherein the fiber reinforcedplastic includes a carbon fiber reinforced plastic.
 25. The golf clubhead according to claim 2, wherein the fiber reinforced plastic includesa carbon fiber reinforced plastic.
 26. The golf club head according toclaim 18, wherein the fiber reinforced plastic includes a carbon fiberreinforced plastic.
 27. The golf club head according to claim 19,wherein the fiber reinforced plastic includes a carbon fiber reinforcedplastic.